Fluid actuated percussive tool



FeB. 23,A l`912. c. c. HANSEN Lm FLUID ACTUATED PERCUSSIVE TOOL Filed Sept. 6, 1929 -pointed Patented Feb. 23, 1932 UNITED STATES PATENT voFFlcE CHARLES C. HANSEN, OF EASTON, PENNSYLVANA, ASSIGNOR T0 INGERSOLL-RAND COMPANY, 0F JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY FLUID' ACTUATED PERCUSSIVE TOOL Application filed September 6, 1929. Serial No. 390,751.

This invention relates to fluid actuated percussive tools, but more particularly to tools of this type adapted to be used for submarine work. v

One object of the invention is to prevent the admission of foreign matter, such as water and entrained solids, into the tool.

Another object is to utilize the uid exhausting vfrom the piston chamber for `this purpose. i

Still another object is to enable the tool to be started and stoppedwithout requiringl the manipulation o means other than the tool itself, Y

Other objects of the invention and its advantages will be in part obvious and in part out in the following description taken in conjunction with the accompanying drawings, in which Figure 1 is a. sectional elevation of a. per- `cussive tool constructed in .accordance w1th `the practice of the invention,

and showing the position of the percussive elements durin the operative period of the tool, and

igure 2 is a similar view showing the position which the percussive parts assume durin the inoperative period of the tool.

eierring more particularly to the drawings, theinvention is shown, for the purpose of illustration, as being embodied in a per-l cussive tool adapted' for driving piles and similar articles which, during the course' of the oleration, may become submerged as may also t e percussive tool used for driving it.

The percussive tool illustrated comprises ac linder A having a piston chamber B in which is disposed'a reciprocatoryhammer piston C.l A back head D forms a closure for the rearward end of the cylinder and at thc` forward end of the cylinder is a -ront head E having integral guide plates F at its front end to act as guides for a pile G and to main'- tain the tool in the correct operative position on the pile. p c

The back head D and the front head E may be secured to the cylinder A in any suitable and convenient manner, as for instance, by bolts H.

' The working implement, which in this instance assumes the form of a striking block J,

is disposed in a bore K in the front head E i and has a head L which cooperates slidably with the wall of the bre K. The striking' block has a reduced forward portion OA which is of somewhat smaller diameter than the forward portion oi the bore K to form anannular space P about said reduced portion O.'

On the rearward end of the driw'ng block is a shank Q which projects slidably through a bore R in the front` end of the cylinder A and extends normally a sufficient distance into the front end of the piston chamber B to prevent the'close approach of the piston C to the front wall of said piston chamber'B.

The piston C may be of a well known type having ahead S to impact against the "shank Q of the driving block, and said piston carries at its rearward end a stem T which extends slidably 4into Aa reduced portion U of the 4piston'chamber B. Asis customary in pis- "I0 tons of this type the stern T controls the distrlbution of pressure fluid to the piston chamber and the rearward end of said stem is conv stantly exposed to\pressure Huid which may .be conveyed into the rearward end of the piston chamber by a passage V communicating with al connection W which may lead from a source of pressure fluid supply.

Adjacent the` head S of the piston and on the stem T is a reduced portion or neck X which, when the piston C approaches its rearward limiting position luncovers a port Y in the reduced portion ofthe piston chamber for admitting pressure iluid rearwardly of the head S to assist that acting against the stem T for driving the piston C forwardly against the working implement. The port Y is preferably located near the front end of the reduced portion U and is constantly in communication with the pressure fluid supply through a passage Z.

- The admission of pressure Huid tothe front l end of the pistonchamber B Jfor driving'the piston C rearwardly is also effected by the stem conveyed to this end of the piston chamber by a frontinlet passage b which has its inlet opening or -port c in the reduced portion U of the piston chamber and its outlet opening T of the piston.; Such pressure iiuid is ,I

or port d in the frontend of the piston chamr Preferably the outlet opening d isso located that when the working implement J lies in the upper or rearward end of the bore K the back end of the shank Q will lie substantially in the same transverse plane as the port d so that the piston C will be prevented from overrunning the said'port d. The exhaust fluid from the piston chamber B is conveyed therefrom by an exhaust' passage or passages e which lead from a point rearwardly of the transverse median line of the piston chamber B to the bore K from whence the exhaust may flow through the space P and thence to the atmosphere',- orv to the water if submerged, between the guide fthe bore.

plates F or through ports f in the guide plates F.

f The passage or passages' e provide an outlet 'ifor the exhaust fluid from only the rearward end of the piston chamber B, and in order to direct the exhaust fluid from the front end of the piston chamber through the same channels the cylinder A is further provided with an exhaust port or ports g which lead from a pointforwardly of the transverse median line of the piston chamber B to the exhaust passage e. Both the exhaust passages e and the ports g are controlled by the piston C. i

In order to arrest the movement of the piston C during such times when the tool is in the inoperat1ve position with respect to thework, the cylinder A is provided with a leak port h lwhich may lead from thefront inlet passage b into the piston chamber at a oint intermediate the exhaust passage e an the exhaust port g. The leak ort 71, is preferably so located that during the normal operation of the tool it will remain constantly covered by the piston C.

In order t0 enable the tool to be readily shifted from one position to another, an eyebolt 7' may be threaded into the back head D and to said eye-bolt may be attached a cable c or similar means whereby the tool may bev raised and lowered or shifted laterally on the work.

The operation of the device isasfollows: Let it be assumed that the tool is about to be loweredto rest on the end of a submerged pile for driving it into the soil and let it further he assumed that the piston chamber has been placed in communication with the pressure iuid supply. Under these conditions the pressure Huid acting against'the rearward end of the stem T will drive the piston C forwardly the front wall of the piston 'chamber. The piston may readily assume this position since then the working implementrwill occupy its lowermost limiting position so that the shank Q of the working plerrient will withdrawn from the piston chamber.

piston chamber. --Alsorinjhis position of the piston the leak port h will bewuncovered-so that pressure fluid may then flow directly from the inlet passage b through lthe leak port h into the piston chamber B to act against the rearward end of the piston C for holding it in its foremost position. iSuch iiuid will then flow through the exhaust passage cinto the bore K and thence through the space P to form an annular jet about the reduced portion O of the workin implement for preventing the admission o water into As the tool is lowered into position and the working implement. contacts with the-pile G, the 'weight of the tool will overcome the ressure acting against the rearward end o .-the piston and the shank Q. will move the piston Crearwardly in the piston chamber to cover the leak port 71,. Upon continued lowering of the toolthe port d of the inlet passage b will be `uncovered by the piston so that pressure fluid will flow into the front end of the piston chamber to set the piston in operation.

During the normal operation of the piston the pressure fluid utilized for actuating it Vwill flow through the exhaust passage or passages e into the bore K and thence through the space P of the water surroun ing the tool. In this way the exhaust fluid the admission of water into the bore during the operation of the tool. l

After the pile- G has been driven thedescribed depth, the tool mayagain be raised and the parts will-assume the positions illustrated in Figure 2. The piston C will then again occupy the foremost extreme position in the piston chamber and pressure fluid will flow through the leak port k and through the ill prevent channels connecting it vwith the bore K and V chamber and pressure fluid distri uting y mechanism in constant communication with a source of lluid supplv` said cylinder having inlet passages for introducing pressure lui into the piston chamber` a hammer piston in the cylinder controlling the outlet opening of one inlet passage and thps' the idle and oper- .ating periods of the tool, a front head having a bore, means in the ore adapted tb be actuated by the hammer iston,vand passages for introducing fluid, from the-piston chamber intothe bore vto prevent the entrance of foreign matter into the bore both the operating and idle periods of the tool.

' 2. In a Huid actuatedv percussive tool, the

ed to cover said inlet passage and there y discontinue the operation of the tool, a ,front head having a bore, means in the bore adapted to `be actuated-by the hammer piston,

an exhaust passage for conveying exhaust liuid from the piston chamber into the bore to prevent entrance of foreign matter into the bore, and a leak port in the cylinder to supply pressure fluid to the bore for preventing the entrancevof foreign matter into the bore during the i'dle period of the tool.

3. In a fluid actuated percussive tool', the combination of a cylinder having a piston chamber and pressure fluid distributing mechanism in constant communication with a source of fiuidsupply, said cylinder having inlet passages for introducing pressure fluid into the piston chamber, a hammer pis'- ton in the cylinder controlling the outlet opening of one inlet passage and being ada ted to cover said inlet passage and=there y discontinue the operation of the tool, a front head having a bore, means in the lbore adapted to be actuated by the hammer pistonA and having a portion of smaller diameter thanA the bore, an exhaust passage for conveying exhaust fluid from the piston chamber into the bore to form an annulus of exhaust fluid around the reduced portion for preventing the entrance offoreignmatter into the bore,

and a leak port in the cylinder to supply pressure fluid to the bore for preventing the entrance of foreign matter into the bore during the idle period of the tool. -v

4. In a fluid actuated percussivetool, the combination of a cylinder having a piston chamber and pressure fluid distributing mechanism in constant communication with a sourcefof fluid supply, said cylinder having ports and passages for introducing pressure fluid into the piston chamber, a hammer piston in the cylinder controlling the outlet opening of one inlet passage and being adapted to cover saidinlet passage and thereby discontinue the Yoperation of thetool, a front head -having Va bore, means therein adapted to be actuated by the hammer piston and cooperating with the bore to form a space around said means, an exhaust passage for conveying exhaust fluid from the .piston chamber into the said space to prevent the entrance of foreign matterjnto the bore,'and a leak port in the cylinder to supply pressure fluid to the bore for preventing the entrance Y ofvforeign matter into the bore during the idle period of the tool.

5. In a fluid plement exhaust passage combination of a cylinder having a piston chamber and a hammer piston therein, said cylinder having ports and passages including a front inlet passage for introducing pressure fluid into the piston chamber, a front head having a bore, a working implement in the bore and normally limiting the forward movement of the hammer piston to prevent said hammer piston from overrunning the inlet passage, said Working implement having a guiding portion and a4 reduced portion of smaller diameterthan the bore, an exhaust passage for conveying exhaust fluid from the piston chamber into the bore adjacent-the reduced portion to prevent the entrance of foreign matter into the bore, and a leak port in the cylinder for admitting pressure fluid into the piston chamber to hold the-piston in fixed position over the inletpassage uponretraction of the Working imand to supply pressure fluidto'the the entrance of foregn matter into the bore during the idle period of the tool.

v 6. In a fluid actuated percussive tool, the combination of a cylinder having a piston chamber andra hammer piston thereimsaid` cylinder having ports and passages including a front inlet passage for introducing pressure fluid into the piston chamber, a front head into the piston chamber to normally prevent the hammer piston 'from overrunning the inlet passage, said Working implement having a guidingv portion and a forward reduced portion of smaller -diameter thanthel bore, an exhaust passage for conveying exhaust fluid from th-e piston chamber into the bore adjacent the reduced portion to prevent the entrance of foreign matter into the bore during the operation and-the bore for preventing having a bore, aworking implement in the bore and having a shank portion extending ofthe tool; and a leak port leading from the front inlet passage into the piston chamber to hold the piston in fixed position overv the inlet passage upon retraction of the shank and to supply pressure fluid to the exhaust passage and the bore for preventing the entrance of foreign matter into the bore during the idle period of the tool. 7. A'fluid actuated percussive tool, comprisinga cylinder having `inletrand exhaust passages anda piston chamber, a front inlet port for conveying pressure fluid from the` inlet passage to the piston chamber, a hammer piston in the piston chamber covering said inlet port during theA idle periodof the tool, and a leak portin the cylinder for conveying pressure fluid from said inlet passage to the exhaust duringthesaid idle period and preventing thereby the entrance of foreign matter into the tool. v

8. A fluid actuated percussive tool, comhaving inlet and exhaust prising'a cylinder passages and a piston chamber, a front inlet actuated percussive tool, the

portV for conveying pressure from the lao inlet passage to the piston chamber, a. hammer piston inthe piston chamber covering said inlet portduring the idle period of the tool, a leak port in the cylinder for conveying pressure fluid from said inlet passage to the exhaust during the said idle period and preventing thereby the entrance of foreign matter into the tool, means limiting the forward movement of the piston during normal operation. of the tool and preventing said piston from overrunning the inlet port, said limiting of the piston movement causing it to cover -the leak port, andan exhaust port for conveying exhaust 'uidt from the piston chamber to the exhaust passage during said normal operation and preventing thereby the entrance of foreign matter into the tool.

` In testimonywhereof I have signed this specication.

CHARLES C. HANSEN. 

